CVE-2023-26049

/// Technical description

Jetty is a java based web server and servlet engine. Nonstandard cookie parsing in Jetty may allow an attacker to smuggle cookies within other cookies, or otherwise perform unintended behavior by tampering with the cookie parsing mechanism. If Jetty sees a cookie VALUE that starts with `"` (double quote), it will continue to read the cookie string until it sees a closing quote -- even if a semicolon is encountered. So, a cookie header such as: `DISPLAY_LANGUAGE="b; JSESSIONID=1337; c=d"` will be parsed as one cookie, with the name DISPLAY_LANGUAGE and a value of b; JSESSIONID=1337; c=d instead of 3 separate cookies. This has security implications because if, say, JSESSIONID is an HttpOnly cookie, and the DISPLAY_LANGUAGE cookie value is rendered on the page, an attacker can smuggle the JSESSIONID cookie into the DISPLAY_LANGUAGE cookie and thereby exfiltrate it. This is significant when an intermediary is enacting some policy based on cookies, so a smuggled cookie can bypass that polic

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References